Machine for sewing concealed slide fasteners



B. DUCHAN March 21, 1961 MACHINE FOR SEWING CONCEALED SLIDE FASTENERSFiled Dec. 16, 1957 2 Sheets-Sheet 1 I INVENTOR.

March 21, 1961 DUCHAN 2,975,739

MACHINE FOR SEWING CONCEALED SLIDE FASTENERS .Filed Dec. 16, 195"! 2Sheets-Sheet 2 4 INVENTOR.

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MACHINE FOR SEWING CONCEALED SLIDE FASTENERS Benjamin Duchan, Bronx,N.Y., assignor to Placket Closing Corporation of America, New York,N.Y., a corporation of New York Filed Dec. 16, 1957, Ser. No. 702,925

4 Claims. (Cl. 112-260) The present invention relates to a machine forsewing concealed slide fasteners, and more particularly to a machine forsewing concealed slide fasteners wherein the sewn-in slide fastenerclosely resembles a seam when the slide fastener is closed, and whereinthe stitching joining the slide fastener to the cloth of the garment towhich it is attached is concealed. v g

The present application is a continuation-in-part patent application ofmy earlier-filed copending patent application Serial No. 692,882 filedOctober 28, 1957 for: Machine And Process For Sewing Concealed SlideFasteners. The machine and process disclosed in my copending patentapplication Serial No. 692,772 comprise the most efiicient machine andprocess for sewing concealed slide fasteners to a garment that hasheretofore been developed. However, I have now discovered that it ispossible to improve the efiiciency of the machine somewhat by curvingthe face plate or needle plate along its free edge, with the needle holebeing disposed within the curvature and closely adjacent to but spacedfrom the curved free edge. Preferably, the curved free edge is arcuatelycurved with the curvature extending across the face plate a sufficientdistance so that such curved free edge is crossed by a transverseprojection of some point Beneaththe curved free edge of the needle plateis a curvedwall conforming to the degree of curvature of the curved edgeof the needle plate,which wall extends vertically for a distanceappreciably greater than the width of the concealed slide fastener whichis to be stitched to the garment by the machine of the presentinvention. Moreover, in'the present invention I utilizea presserfoot'which is arcuately curved along its" outer edge on either vside ofits needle guide hole. The presserrfoot in the machine of my inventionis'superposed above the needle plate and disposed within the curved freeedge of the needle .plate. Preferably the feed. dogin the machine of thepresent invention extends out of -'a transverse slit in the needle Thisinvention has as another object the provision of amachine which can sewconcealed slide fasteners onto juxtaposed cloth at a rapid rate with aminimum of manual operation. a i p This invention has as yet anotherobject the provision of a'machine for sewing concealed slide fastenersonto a cloth so that the line of stitching joining the concealed slidefastener to the cloth is concealed.

This invention has as a further object the provision of a machine forsewing concealed slide fasteners onto cloth in such: manner thatwhen theconcealed 'slide fasteners. are in their closed disposition theappearance of a genuine seam is closely simulated.

Other. objects willfappear hereinafter.

i to

except that the presser foot is removed in order that clarity of.underlying parts may be had.

Figure 3 is a side elevational view of the portion of the machine shownin Figure 1.

.Figure 4 is a front elevational view of the portion of the machineshown in, Figure 1.

Figure 5 is a fragmentary sectional view taken through the presser footand needle plate on the line Figure 1.

Figure 6 is a plan view revealing the manner in which a tape bearingslide fastener elements is stitched to cloth by the machine of thepresent invention in accordance.

with the process of the present invention.

Figure 7 is a sectional view taken on line 7-7 of Figure 6.

Figure 8 is a view demonstrating the appearance of a concealed slidefastener when the same is in its closed disposition attached to cloth bythe process of the present.

invention, said View demonstrating the seam-like appe'arance ofrthcslide fastener. v

Figure 9 is a section taken on line 9-9 of Figure 8.

Figureit) is a view revealing a concealed slide fastener.

which maybe attached to cloth by the machine of the present invention.

Referring to the drawings, and initially to Figures 1" through 5inclusive, the machine of the present invention is designated generallyas 20. Such machine may comprise a single needle lock-stitch sewingmachine. For

stood that the remainder of the machine is of conven tionalconstruction. The machine 29 includes a presser bar 22 in which is heldby means of set screw 24 the presser foot 26. The

presser foot 26 includes a curved, outer edge 28. Be-

' neaththe presser foot 26 is the plate 32, sometimes referred to as thethroat plate, sometimes as the face plate, and referred to herein as theneedle plate 32. The outer .edge 30 of needle plate 32 is arcuatelycurved, as shown particularly in Figure 2. Y

The curved outer edge 28 of the presser foot 26 extends on both sides ofthe needle guide hole or notch 34, the front portion 28a of the curvededge 28 of presser foot 26 advancing to a gentle curved toe 35. As seenfrom Figure l the presser foot 26 is superposed above the needle plate32, with the entire presser foot being disposed above the needle plate32 and within the border outwardly its maximum distance'in the portionof the needle plate 32 which includes the needle hole 36, such needlehole 36 beingspaced from the arcuately curved outer edge 30-by the land80; In the illustrated embodito its heel) and also the major axis of'the slot 38 through i merit, the needle hole'36 is generally ellipticalwith its j major axis running parallel to the major axis of the vpresser foot 26 (extending from the presser foots toe which the feed doglfl'p'rojects upwardly. The degree of curvature of the outeredge 30ofne'edle plate'32is such that aprojection of the major axis of theelliptical needle hole 36 intersects the curved outer edge30both aovwscbefore the needle hole 36 and after the needle hole 36 (see pointsrespectively designated A and B in Figure 2).

As seen in Figure 3 the needle plate 32 is arcuately curved, with theneedle hole 36 being disposed at the highest point of such arcuatecurvature. The needle plate 32 is secured to the post 42 by front andrear retention screws 44 and 46.

A work plate or end plate 48 of conventional construction is provided atthe top of post 42 for permitting access to the contents of the post 42,such as the bobbin.

The needle plate 32 includes a dependent wall 50 beneath its curvedouter edge 36, which dependent wall 50 is arcuately curved to the sameextent as the outer edge 39 of needle plate 32. Preferably the outerwall 52 of post 42 is similarly arcuately curved so that a curved wallextends vertically beneath the curved outer edge 30 which conforms tothe degree of curvature of the curved outer edge 30. As seenparticularly in Figure 7 the vertical height of this curved outer wallis appreciably greater than the maximum width of the slide fastenerelements which are to be stitched to the cloth by the machine 2% of thepresent invention.

A needle of conventional structure is carried by the needle bar 56 andis reciprocally movable through the needle guide hole 34 of presser foot26 and the needle hole 36 of needle plate 32.

Preferably the machine of the present invention should employ theprocess disclosed in my copending patent application Serial No. 692,772.The manner in which such process may be effected, namely the manner inwhich a concealed slide fastener may be sewn to cloth in accordance withthe present invention is shown particularly in Figures 6 and 7.

A form of concealed slidc fastener 58 which maybe utilized in accordancewith the present invention is shown in Figure 10. The preciseconstruction of the concealed slide fastener 58 forms no part'of thepresent invention, a wide variety of such concealed slide fastenersbeing described in the art. A suitable example of a concealed slidefastener which may be utilized in the present invention is that shown inUnited States Letters Patent 2,738,560 issued March 20, 1956 to JacquesHug entitled Concealed Slide-Fasteners. The finished sewn article isshown in Figures 8 and 9, and by reference to Figures 9 and 10, asufficient understanding of the concealed slide fasteners structure maybe had to follow the manner in which such concealed slide fastener 58 issewn to the cloth 6t).

The slide fastener 58 includes a pair of element supporting tapes 62 and64 on which the elements 66 of the concealed slide fastener 58 arecarried.

As seen particularly in Figure 9, the elements 66 are carried onfolded-in inner edges of the tapes 62 and 64, the inner edges of thetapes 62 and 64 being welted at 68 to provide means for anchoring theelements 66. Since the elements 66 are disposed behind the inner edgesof the tapes 62 and 6d and since the slider 7t) rides on the inside andoutside of the elements 66, when the concealed slide fastener 58 isclosed (see Figure 8) substantially only the tab 72 of slider 76 isvisible.

As shown in Figures 6 and 7, a tape 62 of concealed slide fastener 53 isjoined to the cloth 60. The cloth 69 includes a sewn seam 74 below theconcealed slide fastener '58 and a sewn seam 76 above the concealedslide fastener 58, such seams joining the cloth 60 together except forthe gap intermediate the seams '74 and 76 which is occupied by theconcealed slide fastener 58.

The cloth 60' is folded back along fold line 78 (see Figure 7) toform'the exposed major portion of the cloth designated 66a and thefolded-under portion of the cloth designated 6912, such folded-underportion 66b being juxtaposed to the tape 62.

As seen particularly in Figure 7 the distance between 28 of presser.foot 26 in the region of the needle guide hole 34 of presser foot 26 isapproximately equal to the lateral dimension of the elements 66.Similarly, the maximum width of the land 80 between the needle hole 36and the outer edge 39 of the needle plate 32 is also approximately equalto the lateral dimension of the elements 66, and in any event issufficiently large so that it forms a supporting surface upon theelements 66 may be rested, with a portion thereof overhanging thevertical wall 50 which depends from the outer edge 30 of needle plate32.

The line of stitching 82 is secured closely adjacent the elements 66since the needle guide hole 34 of presser foot 26 is closely adjacentthe outer edge 28 of presser foot 26. In this manner both of the tapes62 and 64 may be secured to the cloth 60 by lines of stitching which areclose to and parallel to the elements 66 carried by such tapes 62 and64.

The inward curving of the outer edge 28 on either side of the needleguide hole 34 of presser foot 26 enables the presser foot to be usedwith the elements 66 advanced by the feed dog 4! very close to theneedle guide hole 34 and the needle hole 36. Similarly, the arcuatecurvature of the outer edge 30 of the needle plate 32 enables theelements 66 to be rapidly fed, and the line of stitching 82 achieved, asclose as possible to the elements 66. The small land portion 36 of theneedle plate 32 enables the elements 6-6 to be supported while the lineof stitching 82 is inserted.

The arcuately curved dependent wall 50 of needle plate 32 and theadjacent outer wall 52 of post 42 enables the slide fastener 53 to befed in respect to the machine 20 without interference to its rapidfeeding, and without interference to the method of insertion heretoforedescribed and which forms the process described in my copending patentapplication Serial No.

Folding back of the major portion 66a over the foldedunder portion 60!)will conceal the line of stitching 32 so that such line of stitching 32may not be seen when the outside of the cloth 60 is viewed (see Figure8).

The present invention may be embodied in other specific forms withoutdeparting from the spirit or essential attributes thereof and,accordingly, reference should be made to the appended claims, ratherthan to the foregoing specification as indicating the scope of theinvention.

I claim:

1. In a sewing machine for sewing concealed slide fasteners, an arcuateneedle plate, said needle plate having a needle hole in the uppermostpoint and closely adjacent the outer edge thereof, said outer edge ofsaid needle plate being inwardly curved on either side of said needlehole when viewed from a position above said needleplate, a presser footsuperposed above said needle plate, said presser foot having a needleguide notch on the outside edge thereof, and said presser foot beingdisposed over said needle plate with the needle guide hole of saidpresser foot mating with the needle hole of said needle plate and theoutside edge of said presser foot being above said needle plate andspaced inwardly a short distance from the outer edge of said needleplate, said needleplate extending downwardly from diametrically oppositepoints on said needlehole, said diametrically opposite points forming aline substantially parallel to the longitudinal axis of said presserfoot.

2. In a sewing machine for sewing concealed slide fasteners, an arcuateneedle plate, said needle plate having an elliptical needle hole in theuppermost point and closely adjacent the outer edge thereof, said outeredge of said needle plate being inwardly curved on either side of saidneedle hole when viewed from a position above said needleplate, anupright wall depending from the lowermost surface of said outer edgeconformed to the shape of said outer edge, a presser foot superposedabove said needle plate, said presser foot having a needle guide notchon the outside edge thereof, said presser foot being disposed over saidneedle plate with the needle guide hole of said presser foot mating withthe needle hole of said needle plate and the outside edge of saidpresser foot being above said needle plate and spaced inwardly a shortdistance from the edge of said needle plate, said needleplate extendingdownwardly fromdiametrically opposite points on said needlehole, saiddiametrically opposite points forming a line substantially parallel tothe longitudinal axis of said presser foot.

3. A sewing machine in accordance with claim 2 in which the outer edgeof the needle plate curves inwardly a suflicient distance so that itcrosses a line which projects from the needle hole and which is parallelto the major axis of the presser foot.

4. In a sewing machine for sewing concealed slide fasteners, an arcuateneedle plate, said needle plate having a a needle hole in the uppermostpoint and closely adjacent ing therethrough on the side of the needlehole opposite to the outer edge thereof, a feed dog extending upwardlythrough said slot, the uppermost surface of said feed dog being belowsaid uppermost point on said needleplate at all times, a presser footsuperposed above said needle plate, said presser foot having a needleguide notch in the outer edge thereof, said presser foot being disposedover said needle plate with the needle guide hole of said presser footmating with the needle hole of said needle plate and the outside edge ofsaid presser foot being above said needle plate and spaced inwardly ashort distance from the outer edge of said needle plate, saidneedleplate extending downwardly from diametrically opposite points onsaid needlehole, said diametrically opposite points forming a linesubstantially parallel to the longitudinal axis of said presser foot.

References Cited in the file of this patent UNITED STATES PATENTS149,714 Brewster Apr. 14, 1874 555,476 Fogg Feb. 25, 1896 1,109,455Onderdonk Sept. 1, 1914 1,387,143 Flanagan Aug. 9, 1921 1,685,854McLaughlin Oct. 2, 1928 2,363,976 Kline Nov. 28, 1944 2,776,635Blumenkrantz Ian. 8, 1957 FOREIGN PATENTS 359,771 Great Britain Oct. 29,1931

